Champion swimmer Michael Phelps won his first race after coming back from suspension at the Mesa Pro Series meeting here in Arizona.
The 29-year-old, considered as one of the most decorated Olympians of all time with 22 medals, was banned for six months in October 2014 after being arrested for drunk driving, reports BBC.
The American clocked 52.38 seconds ahead of arch rival Ryan Lochte (53.11) in the 100m butterfly.
It was not amongst the top 10 world times this year but Phelps said: "I hope we'll be able to build and build."